An investigation into the practical application of the radioimmunoassay (RIA) test of milk progesterone to improve artificial insemination (AI) management in diary cattle

ThesisReproductive performance is one of the most important factors determining profitability in dairy herds (Lamming & Darwash, 1998). Current intercalving intervals (an indicator of reproductive performance) are generally too long for optimal milk production and the number of progeny born per year. These long intercalving intervals may be associated with managerial influences, such as breeding policy or the detection of oestrus or fertility problems, such as acyclia or "repeat breeders" i.e. the problem cow syndrome. Esslemont and Kossaibati (1998) suggested repeat breeding to be caused by an inadequate supply of the hormone progesterone, during the luteal phase of the oestrous cycle and Erb eta/. (1976) found that unsuccessful inseminations were often accompanied by asynchronies in the hormonal profiles. Levels of and patterns of especially progesterone secretion could thus be one of the underlying causes of repeat breeding in problem cows. The hormone progesterone is produced by a transient organ, which develops in the ovary, after ovulation, called the corpus luteum (CL). The CL functions for a specific period of time (19-22 days after AI) and, if conception does not occur, undergoes regression. If conception does occur, however, the CL continues to function and secrete progesterone throughout the gestation period. Thus the concentration of progesterone in the body flu ids can vary according to the reproductive status of the animal (Ball & McEwen, 1998) and the measurement of progesterone levels in plasma is a specific indicator f . IERSfN 0 luteal functton (Becket a/., 1996). The presence of progesterone in cow milk was first Williams (1991) and Bloomfield eta/. (1986). Laing and Heap (1971) realised that, if progesterone levels in milk were closely correlated wi h those in the plasma, · great benefits would accrue to physiology, because of the relative ease of collecting milk rather than blood samples. Progesterone in milk was positively identified by Heap eta/. (1973) and high correlations (r = 0.91) with progesterone levels in milk and plasma were recorded by Hoffman et a/. (1976) and Peters (1984). This led to the development of sophisticated techniques to measure milk progesterone levels by Cox eta/. (1978) and identify the physiological status of the animal. As a result milk progesterone profiles and individual milk sample measurements can now be used to monitor the luteal and hence ovarian activity of pregnant cows (Pursley eta/., 1997b). Milk progesterone analysis may thus been seen as a most convenient method of monitoring ovarian activity in dairy cows and the possibility to use this technique as a routine procedure for pregnancy diagnosis service to commercial dairy producers may be possible. The objective of this study was to: a) test the accuracy of pregnancy diagnosis with the aid of a milk progesterone concentration assay b) use the milk progesterone assay to evaluate the progesterone profiles of cows classified as problem (low fertile) cows and c) determine a strategy to solve the incidence of problem low fertile cows, relating to information acquired from the milk progesterone assay

Developing and evaluating a method for multi-ovulation and embryo transfer (MOET) in the bison (bison bison)

ThesisThe idea of domesticating bison is a goal for some cattlemen, who believe in utilizing the hardiness, long life, foraging habits and feed conversion abilities of the bison in the production of animal protein. It was not until the population of millions of bison, that once roamed the USA ranges, had been reduced to only a few hundred head, that anybody seriously took an active interest in restoring the numbers of these unique animals. Reproductive studies on the bison have shown that anatomically and physiologically they are very similar to domestic cattle. One notable difference is the apparent seasonality (Table 2.1) of the bison. Bison breeders indicate that bison are seasonally polyestrous, having a cycling season during the late summer and continuous into late autumn. Other bison breeders consider the breeding season to be shorter, ranging from summer to autumn. This observed shorter duration may be partly due to the fact that increased breeding activity is observed only during the early part of the season. Cows that do not conceive early in the season, often do not become pregnant as they are subjected to the stress of winter and the consequent decrease in the quality and quantity of nutrition. Anatomically, bison have small ovaries and reproductive tracts, which could be compared to that of first-calf beef heifers. Consequently, follicles and CL's are smaller and more difficult to identify by rectal palpation. Problems associated with the use of reproductive techniques, such as superovulation and embryo transfer in the bison, are not the technologies as such, but the handling and management of the animals. Most bison are not amenable to domestication and are managed as wild animals. The bison therefore responds accordingly and are often dangerous when handled. The stress encountered during these procedures on the animal is also a factor that could affect the response of the bison to superstimulation. A compounding problem with the few animals still left in the early 1900's, hints that the bison can experience a serious inbreeding problem. This problem has led to early abortions and birth defects in many cases. A need has therefore arisen to increase the number of bison in order to create various bloodlines. One of the more economical and feasible ways to increase the bison numbers and achieve this goal is by making use of reproductive technologies such as embryo transfer, in vitro fertilization and artificial insemination (AI). Embryo transfer has the advantage of accelerating the rate of genetic progress and increasing the number of offspring produced. This study thus looks at the possibility of using accelerated breeding techniques generally implemented in domestic cattle to help increase the bison numbers and potential meat production

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

State of the climate in 2018

In 2018, the dominant greenhouse gases released into Earth’s atmosphere—carbon dioxide, methane, and nitrous oxide—continued their increase. The annual global average carbon dioxide concentration at Earth’s surface was 407.4 ± 0.1 ppm, the highest in the modern instrumental record and in ice core records dating back 800 000 years. Combined, greenhouse gases and several halogenated gases contribute just over 3 W m−2 to radiative forcing and represent a nearly 43% increase since 1990. Carbon dioxide is responsible for about 65% of this radiative forcing. With a weak La Niña in early 2018 transitioning to a weak El Niño by the year’s end, the global surface (land and ocean) temperature was the fourth highest on record, with only 2015 through 2017 being warmer. Several European countries reported record high annual temperatures. There were also more high, and fewer low, temperature extremes than in nearly all of the 68-year extremes record. Madagascar recorded a record daily temperature of 40.5°C in Morondava in March, while South Korea set its record high of 41.0°C in August in Hongcheon. Nawabshah, Pakistan, recorded its highest temperature of 50.2°C, which may be a new daily world record for April. Globally, the annual lower troposphere temperature was third to seventh highest, depending on the dataset analyzed. The lower stratospheric temperature was approximately fifth lowest. The 2018 Arctic land surface temperature was 1.2°C above the 1981–2010 average, tying for third highest in the 118-year record, following 2016 and 2017. June’s Arctic snow cover extent was almost half of what it was 35 years ago. Across Greenland, however, regional summer temperatures were generally below or near average. Additionally, a satellite survey of 47 glaciers in Greenland indicated a net increase in area for the first time since records began in 1999. Increasing permafrost temperatures were reported at most observation sites in the Arctic, with the overall increase of 0.1°–0.2°C between 2017 and 2018 being comparable to the highest rate of warming ever observed in the region. On 17 March, Arctic sea ice extent marked the second smallest annual maximum in the 38-year record, larger than only 2017. The minimum extent in 2018 was reached on 19 September and again on 23 September, tying 2008 and 2010 for the sixth lowest extent on record. The 23 September date tied 1997 as the latest sea ice minimum date on record. First-year ice now dominates the ice cover, comprising 77% of the March 2018 ice pack compared to 55% during the 1980s. Because thinner, younger ice is more vulnerable to melting out in summer, this shift in sea ice age has contributed to the decreasing trend in minimum ice extent. Regionally, Bering Sea ice extent was at record lows for almost the entire 2017/18 ice season. For the Antarctic continent as a whole, 2018 was warmer than average. On the highest points of the Antarctic Plateau, the automatic weather station Relay (74°S) broke or tied six monthly temperature records throughout the year, with August breaking its record by nearly 8°C. However, cool conditions in the western Bellingshausen Sea and Amundsen Sea sector contributed to a low melt season overall for 2017/18. High SSTs contributed to low summer sea ice extent in the Ross and Weddell Seas in 2018, underpinning the second lowest Antarctic summer minimum sea ice extent on record. Despite conducive conditions for its formation, the ozone hole at its maximum extent in September was near the 2000–18 mean, likely due to an ongoing slow decline in stratospheric chlorine monoxide concentration. Across the oceans, globally averaged SST decreased slightly since the record El Niño year of 2016 but was still far above the climatological mean. On average, SST is increasing at a rate of 0.10° ± 0.01°C decade−1 since 1950. The warming appeared largest in the tropical Indian Ocean and smallest in the North Pacific. The deeper ocean continues to warm year after year. For the seventh consecutive year, global annual mean sea level became the highest in the 26-year record, rising to 81 mm above the 1993 average. As anticipated in a warming climate, the hydrological cycle over the ocean is accelerating: dry regions are becoming drier and wet regions rainier. Closer to the equator, 95 named tropical storms were observed during 2018, well above the 1981–2010 average of 82. Eleven tropical cyclones reached Saffir–Simpson scale Category 5 intensity. North Atlantic Major Hurricane Michael’s landfall intensity of 140 kt was the fourth strongest for any continental U.S. hurricane landfall in the 168-year record. Michael caused more than 30 fatalities and $25 billion (U.S. dollars) in damages. In the western North Pacific, Super Typhoon Mangkhut led to 160 fatalities and$6 billion (U.S. dollars) in damages across the Philippines, Hong Kong, Macau, mainland China, Guam, and the Northern Mariana Islands. Tropical Storm Son-Tinh was responsible for 170 fatalities in Vietnam and Laos. Nearly all the islands of Micronesia experienced at least moderate impacts from various tropical cyclones. Across land, many areas around the globe received copious precipitation, notable at different time scales. Rodrigues and Réunion Island near southern Africa each reported their third wettest year on record. In Hawaii, 1262 mm precipitation at Waipā Gardens (Kauai) on 14–15 April set a new U.S. record for 24-h precipitation. In Brazil, the city of Belo Horizonte received nearly 75 mm of rain in just 20 minutes, nearly half its monthly average. Globally, fire activity during 2018 was the lowest since the start of the record in 1997, with a combined burned area of about 500 million hectares. This reinforced the long-term downward trend in fire emissions driven by changes in land use in frequently burning savannas. However, wildfires burned 3.5 million hectares across the United States, well above the 2000–10 average of 2.7 million hectares. Combined, U.S. wildfire damages for the 2017 and 2018 wildfire seasons exceeded $40 billion (U.S. dollars)

Effects of the organophosphate fenthion for control of the red-billed quelea Quelea quelea on cholinesterase and haemoglobin concentrations in the blood of target and non-target birds

The red-billed quelea bird Quelea quelea is one of sub-Saharan Africa’s most damaging pests, attacking small-grain crops throughout semi-arid zones. It is routinely controlled by spraying its breeding colonies and roosts with organophosphate pesticides, actions often associated with detrimental effects on non-target organisms. Attributions of mortality and morbidity of non-targets to the sprays are difficult to confirm unequivocally but can be achieved by assessing depressions in cholinesterase activities since these are reduced by exposure to organophosphates. Here we report on surveys of birds caught before and after sprays that were examined for their blood cholinesterase activities to assess the extent to which these became depressed. Blood samples from birds were taken before and after sprays with fenthion against red-billed quelea in colonies or roosts, and at other unsprayed sites, in Botswana and Tanzania and analysed for levels of haemoglobin (Hb) and activities of whole blood acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). Background activities of AChE, BChE and Hb concentrations varied with bird species, subspecies, mass, age and gender. Contrary to expectation, since avian erythrocytes are often reported to lack cholinesterases, acetylcholinesterase activities in pre-spray samples of adult birds were positively correlated with Hb concentrations. When these factors were taken into account there were highly significant declines (P\0.0001) in AChE and BChE and increases in Hb after contact with fenthion in both target and non-target birds. BChE generally declined further (up to 87 % depression) from baseline levels than AChE (up to 83 % depression) but did so at a slower rate in a sample of quelea nestlings. Baseline activities of AChE and BChE and levels of Hb were higher in the East African subspecies of the red-billed quelea Q. q. aethiopica than in the southern African subspecies Q. q. lathamii, with the exception of BChE activities for adult males which were equivalent

Characterization of the human myelin oligodendrocyte glycoprotein antibody response in demyelination

Over recent years, human autoantibodies targeting myelin oligodendrocyte glycoprotein (MOG Ab) have been associated with monophasic and relapsing central nervous system demyelination involving the optic nerves, spinal cord, and brain. While the clinical relevance of MOG Ab detection is becoming increasingly clear as therapeutic and prognostic differences from multiple sclerosis are acknowledged, an in-depth characterization of human MOG Ab is required to answer key challenges in patient diagnosis, treatment, and prognosis. Herein, we investigated the epitope, binding sensitivity, and affinity of MOG Ab in a cohort of 139 and 148 MOG antibody-seropositive children and adults (n = 287 patients at baseline, 130 longitudinal samples, and 22 cerebrospinal fluid samples). MOG extracellular domain was also immobilized to determine the affinity of MOG Ab. MOG Ab response was of immunoglobulin G1 isotype, and was of peripheral rather than intrathecal origin. High affinity MOG Ab were detected in 15% paediatric and 18% adult sera. More than 75% of paediatric and adult MOG Ab targeted a dominant extracellular antigenic region around Proline42. MOG Ab titers fluctuated over the progression of disease, but affinity and reactivity to Proline42 remained stable. Adults with a relapsing course intrinsically presented with a reduced immunoreactivity to Proline42 and had a more diverse MOG Ab response, a feature that may be harnessed for predicting relapse. Higher titers of MOG Ab were observed in more severe phenotypes and during active disease, supporting the pathogenic role of MOG Ab. Loss of MOG Ab seropositivity was observed upon conformational changes to MOG, and this greatly impacted the sensitivity of the detection of relapsing disorders, largely considered as more severe. Careful consideration of the binding characteristics of autoantigens should be taken into account when detecting disease-relevant autoantibodies